Patent Literature 1 discloses a transmitter in which a detection circuit is shared by a plurality of transmission circuits that differ from each other in use frequency band.
With the use of a technique disclosed in Patent Literature 1, however, it is impossible to individually detect transmission signals which are simultaneously generated by a respective plurality of transmission circuits in order to carry out multicarrier communication, a carrier aggregation, or the like.
According to a communication device disclosed in Patent Literature 2, on the other hand, when a detection circuit is provided for each frequency band, it is possible to detect each of levels of a respective plurality of transmission signals which are simultaneously generated.